Both Great Britain's women's and men's teams took a big step towards securing their places at Tokyo 2020 with healthy wins in the first legs of their Olympic qualifying play-offs.
The defending Olympic champion women's side beat Chile 3-0 through goals from Izzy Petter, Hannah Martin and Anna Toman at Lee Valley in London.
The men's team came back from a goal down to defeat Malaysia 4-1.
Both sides play their second legs at the same venue on Sunday.
"We're pleased with the result but it's job half done - there will be absolutely no complacency, we know we're not qualified yet," women's captain Hollie Pearne Webb told BBC Sport.
"We started tentatively, the nerves showed and there is plenty to improve on.
"Hopefully the nerves will have gone by then, it's a fresh start."
Having been through a transitional period since the last Olympics, the women's side came into the weekend knowing this is their last chance to qualify to defend the title they won at Rio 2016.
The game was goalless at half-time but Petter's backhand strike from just inside the circle for her third international goal gave the nervous hosts a much-needed lead.
Britain dominated the world number 18 side after going in front and doubled their advantage in the 45th minute when Martin forced in Petter's cross from close range.
Toman's deflected penalty corner strike with seven minutes to go made it 3-0 and put Great Britain in a great position to qualify, with the side with the the highest aggregate score across the two legs taking a place at the Games.
Strong second half puts Britain in command
Britain's men also started their crucial play-off in nervous fashion, trailing 1-0 at half-time following a lovely finish from Malaysia's Nabil Noor.
But Sam Ward's 70th international goal three minutes after the break sparked a strong second-half display where Great Britain scored four times in 14 minutes to take a three-goal lead into the second leg.
After Ward's equaliser, Phil Roper's fierce strike from the top of the circle put Britain in front.
With the hosts firmly on the front foot, Scotland striker Alan Forsyth made it 3-1 in the 42nd minute with a precise strike into the corner.
A first Great Britain goal for James Gall made it 4-1 with 13 minutes left to play and despite a late surge by Malaysia, Danny Kerry's side took the win and a will hold a crucial advantage going into Sunday's decider.
"It's a strange one, we're not used to playing two games in a row and the aggregate score is new to us," said Roper.
"They'll have everything to play for and nothing to lose so they're going to come out hard in the second leg.
"We need to react and be positive but we're confident we can get it done."
Great Britain's women will take on Chile at 12:00 GMT, with the men's game against Malaysia following at 15:00.